Pollen-inferred vegetation and environmental changes since 16.7 ka BP at Balikun Lake, Xinjiang  

作　　者：TAO ShiChen AN ChenBang CHEN FaHu TANG LingYu WANG ZongLi LU YanBin LI ZhiFei ZHENG TongMing ZHAO JiaJu 

机构地区：[1]MOR Key Laboratory of West China's Environmental System, Lanzhou University, Lanzhou 730000, China [2]Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences, Nanjing 210008, China

出　　处：《Chinese Science Bulletin》2010年第22期2449-2457,共9页

基　　金：sup-ported by the National Natural Science Foundation of China (90502008, 40871006 and 40721061);the Program for New Century Excellent Talents in University

摘　　要：A high-resolution fossil pollen record from the sedimentary cores of Balikun Lake, northwestern China, combined with modern surface pollen data, is used to reconstruct the history of vegetation and climatic change since 16.7 cal. ka BP. Fossil pollen assem-blages and lithology indicate that the study area was dominated by desert. The desert had extremely arid climate and lower effec-tive moisture during 16.7–7.9 cal. ka BP, especially from 16.7 to 8.9 cal. ka BP when the lake maybe dried up. During 8.9–7.9 cal. ka BP, the environment gradually recovered in this area. It was then followed by the optimum period from 7.9 to 4.3 cal. Ka BP, when the effective moisture obviously increased. It was characterized by the typical desert-steppe/steppe vegetation and was ac-companied with several patch-birch woodlands around the lake. After that, a short but extremely arid climatic event occurred during 4.3–3.8 cal. ka BP, and the vegetation quickly changed from desert-steppe/steppe to desert. It was a relatively optimum period from 3.8 to 0.53 cal. ka BP showing typical desert-steppe/meadow-steppe landscape. Since 0.53 cal. ka BP, the climate has shown signs of deteriorating again. Furthermore, regional comparison shows that the characteristics of climatic and environmental evolution in this area were clearly different from East Asia monsoonal area during the last 16.7 cal. ka BP. It was characterized by the arid climate during the late-glacial and early Holocene, and relatively wet during the mid-late Holocene.A high-resolution fossil pollen record from the sedimentary cores of Balikun Lake, northwestern China, combined with modem surface pollen data, is used to reconstruct the history of vegetation and climatic change since 16.7 cal. ka BP. Fossil pollen assemblages and lithology indicate that the study area was dominated by desert. The desert had extremely arid climate and lower effective moisture during 16.7-7.9 cal. ka BP, especially from 16.7 to 8.9 cal. ka BP when the lake maybe dried up. During 8.9-7.9 cal. ka BP, the environment gradually recovered in this area. It was then followed by the optimum period from 7.9 to 4.3 cal. Ka BP, when the effective moisture obviously increased. It was characterized by the typical desert-steppe/steppe vegetation and was accompanied with several patch-birch woodlands around the lake. After that, a short but extremely arid climatic event occurred during 4.3-3.8 cal. ka BP, and the vegetation quickly changed from desert-steppe/steppe to desert. It was a relatively optimum period from 3.8 to 0.53 cal. ka BP showing typical desert-steppe/meadow-steppe landscape. Since 0.53 cal. ka BP, the climate has shown signs of deteriorating again. Furthermore, regional comparison shows that the characteristics of climatic and environmental evolution in this area were clearly different from East Asia monsoonal area during the last 16.7 cal. ka BP. It was characterized by the arid climate during the late-glacial and early Holocene, and relatively wet during the mid-late Holocene.

关 键 词：环境变化 巴里坤湖 花粉记录 BP 植被 中晚全新世 新疆 气候变化 

分 类 号：P532[天文地球—古生物学与地层学] P343.3[天文地球—地质学]